Don and cal are high school friends from the same hometown. after high school, don started to work full-time as an overnight cleaner at a floor cleaning business. cal attended a public university nearby and earned a bachelor's degree in marketing. at their 10-year reunion don and cal discuss the courses their lives have taken since they graduated from high school. don has been working full-time for the whole 10 years and makes about $40,000 per year from the cleaning business. cal has been working for 5 years as manager of the marketing department at a health insurance company in the area; he makes about $70,000 per year. what concept would a sociologist use to describe the differences between don and cal?